Carburetors



Oct. 31, 1961 J. J. CYBART, JR

CARBURETORS 2 Sheets-Sheet 1 Filed Nov. 3, 1958 INVENTOR ATTORNEYS Oct. 31, 1961 J. J. CYBART, JR

CARBURETORS 2 SheetsSheet 2 Filed NOV. 3, 1958 United States Patent Ofiflce 3,606,620 Patented Oct. 31, 1961 3,006,629 CARBURETGRS John J. Cybart, Jr., 62 Sunnyside Drive, Shelton, Conn. Filed Nov. 3, 1958, Ser. No. 771,439 Claims. (Cl. 261-549) This invention relates to carburetors for supplying combustible mixtures to internal combustion engines, and has for an object to provide a carburetor of the fuel injector type to do away with the usual needle valves and parts associated therewith employed in the common type of carburetor relying on the suction in the manifold for feeding fuel to the air supply.

Another object is to provide an injector carburetor which will supply a controlled mixture which will decrease waste fuel on deceleration and will increase mileage for a given amount of fuel, and increase efliciency of operation.

Another object is to provide a carburetor which will improve the operation of the motor when starting cold and eliminate the requirement of the rich mixture usually required with the suction type carburetor.

With the foregoing and other objects in view, I have devised the construction illustrated in the accompanying drawings forming a part of this specification. It is, however, to be understood the invention is not limited to the specific details of construction and arrangement shown, but may embody various changes and modifications within the scope of the invention.

In these drawings:

FIG. 1 is a top plan view of my improved carburetor;

FIG. 2 is a vertical section and partial side view looking toward the bottom of FIG. 1;

FIG. 3 is a detail section susbtantially on line 33 of FIG. 2;

FIG. 4 is a side view of a portion of the fuel valve operating means taken substantially on the plane of line 44 of FIG. 2;

FIG. 5 is a side elevation of the carburetor and the operating means for the butterfly and fuel valves;

FIG. 6 is a detail longitudinal section of a portion of the feed valve and adjacent parts;

FIG. 7 is a transverse section thereof taken substantially on line 77 of FIG. 6, and

FIG. 8 is a side view of the carburetor and operative connections to an accelerator control pedal.

This improved carburetor comprises a simple construction doing away with the usual floats and needle valve and associated parts of the common type carburetor which relies on suction of the manifold to draw fuel through the needle valve into the air passage. This improved carburetor, one embodiment of which is shown in the drawings, comprises a body member 10 provided with an air passage including a Venturi tube 11, and connected to the bottom is an air inlet pipe or tube 12 leading to the Venturi passage and in which is a control valve 13, such, for example, as the usual type of pivoted butterfly valve. This may be the lower section of a standard type carburetor. Means is provided for feeding fuel to the air passage be tween the butterfly valve and the intake manifold 14 of the engine comprising a bridge member 15 extending across the narrow part of the Venturi leaving air passages 16 on the opposite sides thereof, and a fuel passage 17 in the body member leading to outlet openings 18 at the opposite sides of this bridge discharging into the passages 16.

Mounted in the body is a valve for controlling feed of liquid fuel under pressure to this passage 17 and therefore to the Venturi between the butterfly valve and the intake manifold. In the device shown the body is provided with a transverse passage 19 opening through the opposite sides of the body, and in this passage is a closefitting hollow sleeve 20 provided with an inlet opening 21 on one side and an outlet opening 22 on another side, preferably the opposite side from the inlet opening, which outlet opening leads to the passage 17. This opening may be of any suitable shape but is preferably an elongated slot. This sleeve is held in its transverse passage by cap members or covers 23 and 24 at its opposite ends, which may be secured to the body over the ends of the sleeve, by suitable securing screws 25. The surfaces of the sleeve and passage are sealed at the opposite ends by suitable packing 26, such, for example, as Teflon seal, to prevent leakage of fuel. Mounted to slide longitudinally in the sleeve 20 is a cylindrical fuel valve 27 provided with a chamber 28 forming a fuel reservoir, and it is open through one side in communication with the fuel inlet opening 21. It is closed at the opposite side by a thin wall 29 over the outlet opening 22, and this closing wall is provided with a series of small holes 30 therethrough spaced from each other longitudinally of the valve and preferably substantially aligned, so that as the valve is shifted inwardly longitudinally, or upwardly as shown in FIGS. 3 and 6, in the sleeve 20, one or more of these holes are brought into alignment with the outlet opening 22 to feed more or less fuel to the passage 17 and therefore to the air passage. Of course, movement of this valve in the opposite direction outwardly or downwardly as viewed in FIGS. 3 and 6 will shift the holes away from alignment with the opening 22 and shut off more or less of the supply of fuel to the passage 17. The fuel valve 27 is sealed in the tube 20 on opposite sides of the chamber 28 by suitable sealing means, such, for example, as the 0 rings 31, and a compression spring 32 tends to shift this valve outwardly or downwardly as viewed in FIGS. 3 and 6, toward the shut-off position, this spring resting at one end against the valve and at the other end against the cap or cover 23. Means is provided for feeding liquid fuel under pressure from any suitable source to the inlet 21, such, for example, as a fuel pump 33 operated by the engine, such a connection being shown at 34, leading to a passage 35 in the body member.

Means is also provided for operating the fuel valve 27 in synchronism with the butterfly valve 13 from a control means, such, for example, as the accelerator pedal 36 of the motor car in which the engine is being used. This may be any suitable type of connection. In the arrange ment shown a link 37 leads from the accelerator pedal to one arm of a bell crank 38 pivoted at 39, with a second link 40 connecting the other arm of this bell crank to a lever 41 pivoted to a support 42 at one side of the body member at 43, and with its other arm connected by a rod 44 to the end of the valve 27. Another link 45 connects the lever 41 to an arm 46 connected to the pivot 47 of the butterfly valve. Therefore the butterfly valve and the fuel valve are operated in synchronism from the control means, such as the accelerator pedal 36, and they are so connected thatopening movement of the butterfly valve 13 will be in synchronism with shifting of the fuel valve 27 inwardly to feed more fuel to passage 17 and the air passage, and vice versa. Movement in the opposite direction will close the butterfly valve and shift the fuel valve outwardly to correspondingly reduce the amount of fuel fed to the air passage. The usual return spring (not shown) will be used with the accelerator pedal, and the reverse movement will be assisted by spring 32 of the fuel valve. The connections between the accelerator pedal and the butterfly and fuel valves and the connections between these valves include adjustable connections, such, for example, as those shown at 48 and 49 which may be employed to adjust the relative movements of the valves and to bring them into proper relation with each other for most eflective combined operations.

It will be seen from the above that when the accelerator pedal is pressed down the fuel valve 27 moves inwardly, bringing into alignment with the opening 22 one or more holes 30 in the closed side 29 of the fuel chamber in this valve to feed fuel into the passage 17 and the air passage, depending on the number of holes which are uncovered by this movement, and also the supply of air to the vacuum chamber through the butterfly valve is increased by opening of this butterfly valve, the two valves being synchronized to provide the proper mixture of air and fuel to be drawn into the intake manifold and engine for the best and most eflicient operation. When the pressure on the accelerator is released the fuel and air valves are shifted toward their closed positions, that is, to positions not entirely cutting off the supply of fuel and air, but permitting passage of suflicient for idling of the motor, although, if preferred, a separate fuel passage for idling purposes could be provided. By synchronizing the fuel injector with the butterfly valve, more positive and accurate ratio of air and fuel for the mixture is made. As this is an injector carburetor with fuel fed to the air supply under pressure, no choke is needed as it does not rely on suction for drawing the supply of fuel into the air stream. The supplying of an unnecessarily rich mixture is therefore eliminated. Also, as this is an injector carburetor, the fuel is vaporized as it is injected under pressure into the air stream, and thus improved starting is effected with a cold motor. Further, reduction in waste fuel is effected on deceleration, as in this device there is a positive shutolf or proportionate reduction of fuel.

Actual use of the carburetor has indicated a cooler running motor and improved efficiency, because there is better and more effective control of the fuel mixture, as a positive relation is maintained between the air supply and the fuel supply. It saves fuel in starting with a cold motor, as the mixture is more accurately controlled than where a vacuum is relied on to draw the fuel into the air stream.

Having thus set forth the nature of my invention, I claim:

1. A carburetor comprising a body including an air passage adapted for connection to an engine inlet manifold, means for feeding fuel to said air passage comprising ,a hollow sleeve mounted in the body provided with an inlet opening in one side and an outlet opening on the other side communicating with a fuel passage leading to the air passage, a sliding valve in said sleeve provided with a chamber open on one side in alignment with the inlet and closed on the opposite side over the outlet, said closed side provided with a series of small holes therethrough spaced from each other longitudinally of the valve, means for connecting the inlet to a supply of fuel under pressure, and means for sliding the valve to bring one or more of the small openings into alignment with the outlet to supply fuel thereto.

2. A carburetor comprising a body including an air passage adapted for connection to an engine inlet manifold and a fuel passage leading to the air passage, a sliding valve mounted in the body provided with a chamber open at one side and closed at the opposite side over the entrance to the fuel passage, said closed side provided with a series of small holes therethrough spaced from each other longitudinally of the valve, a connection from a supply of fuel under pressure to the open side of said chamber, and means for shifting said valve to bring one or more of said openings into alignment with the entrance to the fuel passage to supply fuel thereto.

3. A carburetor comprising a body including an air passage adapted for connection to an engine inlet manifold and a fuel passage leading to the air passage, a control valve in the air passage, means for connecting the fuel passage to a source of fuel under pressure, a valve member provided with a chamber communicating with said fuel passage on one side to receive fuel from said source and provided with a series of small outlet openings from said chamber on another side, means for shifting said valve member to bring one or more of said openings into alignment with the fuel passage to feed fuel to the air passage, a control means, and operative connections from the control means to the air valve and the fuel valve to operate them in synchronism.

4. A carburetor comprising a body provided with an air passage including a Venturi, a butterfly valve in said passage, means for feeding fuel to said Venturi comprising a sleeve mounted in the body having inlet and outlet openings in its side walls, a fuel passage leading from said outlet opening to the Venturi, an inlet connection from a source of fuel under pressure to the inlet opening, a slidable fuel valve in said sleeve provided with a chamber communicating at one side with the inlet opening and closed at the side over the outlet opening, said closed side provided with a series of small spaced holes, means for shifting the fuel valve to bring one or more of said holes into alignment with the fuel passage, a control means, and operative connections from the control means to the air and fuel valves to operate them in synchronism.

5. A carburetor comprising a body provided with an air passage adapted for connection to the intake manifold of an engine, a butterfly valve in said passage, means for feeding fuel to said passage between the butterfly valve and the manifold comprising a fuel passage leading to the air passage, a hollow sleeve mounted in the body provided with inlet and outlet openings in its side walls with the outlet opening leading to the fuel passage, a fuel valve mounted to slide longitudinally in the sleeve provided with a chamber open at one side to communicate with the inlet opening and closed at the side over the outlet opening, said closed side provided with a series of small holes spaced from each other longitudinally of the fuel valve, a supply connection from a source of fuel under pressure to said inlet opening, means for shifting the fuel valve to bring one or more of said holes into alignment with the outlet opening, a control pedal, and operative connections from the control pedal -to the butterfly Valve and the fuel valve operative means to operate these valves in synchronism.

References Cited in the file of this patent UNITED STATES PATENTS 1,746,361 Podszus Feb. 11, 1930 2,269,949 Mallory Jan. 13, 1942 2,632,636 Carson Mar. 24, 1953 2,798,705 Lawrence r v July 9, 1957 

